openssh-agent polling

Darren Tucker dtucker at
Thu Sep 13 22:50:57 EST 2007

Peter Stuge wrote:
> On Thu, Sep 13, 2007 at 04:00:22PM +1000, David Leonard wrote:
>> There is a 10 second parent polling behaviour which is probably
>> what powertop is seeing.. select is using a timeout being the
>> minimum of the poll time (10sec) or the next time a key expires.
> What if you remove the timeout?

The agent will hang around forever after the process it's serving has
gone away, unless a key happens to expire.

also, with regard to having the agent running as the parent, Alan
Jenkins wrote:
> > Damien Miller wrote:
> > ssh-agent starts its command in the parent process probably so that
> >  you can get something useful from $! returned in your startup
> > script,
> Surely that's fixable - wait() gives you the terminated child's exit
> code.

ssh-agent would probably end up as the process group leader too.  I'm
not sure what impact that would have on, eg job control.

Darren Tucker (dtucker at
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

More information about the openssh-unix-dev mailing list